Sewing-machine.



L. BULASKY. SEWING MACHINE. APPLICATION FILI'BD JULY 2, 1913.

Patented Apr. 21, 1914 2 SHEETS-SHEET 1.

IIWE/VTOR WIN/E8858 C a al amvzw ATTORNEYS L. BULASKY.

SEWING MACHINE. APiLIOATION FILED JULY 2, 1913.

Patented Apr. 21, 1914.

2 SHEETS-SHEET 2.

LOUIS BULASKY, on NEW Yonx, N. Y.

SEWING-MACHINE.

Specification of Letters Patent.

Patented Apr. 21, 1914.

Application filed July 2, 1913. Serial No. 776,985.

To all whom it may concern:

Be it known that I, LoUIs BULASKY, a citizen of the United States, residing in the borough of Manhattan of the city of New York, in the State of New York, have invented certain new and useful Improvements in Sewing-Machines, of which the following is aspecification, referencebeing had to the accompanying drawings, forming a part hereof.

This invention relates to sewing machines and seeks to improve generally their construction by improving their .operation, bettering the adjustment of their constituent operating parts and increasing their simplicity whereby the cost of manufacture is reduced and the character of the work improved.

The principal object is to provide a counter-balance for the reciprocating needle bar so as to overcome the great momentum thereof at the time its direction of travel is reversed. The momentum of the reciprocating needle bar in high speed power-driven machines is a factor which has always given;

difficulty in that it brings about a constant pounding and accordingly shortens the period of usefulness of the entire machine and particularly of certain constituent parts which have a strain directly imposed upon them by the needle bar.

This invention aims to improve the operating connections between the main driving shaft and the needle bar, whereby the efficiency of the machine is greatly enhanced.

Reference is now to be had to the accompanying drawings in which?- Figure 1 is a view in front elevation of a sewing machine provided with the present improvements. Fig. 2 is a View in end elevation thereof, taken at the end nearest the needle bar and feeder. Fig. 3 is a plan view of the machine shown in Fig. 1. Fig. 4 is an enlarged detail view, partly in section, showing a fragment of the driving rock shaft for the needle bar and the spring-balance therefor, the rock shaft being shown also as provided with a reciprocable tension bar.

The main parts of the machine herein illustrated are substantially of the usual construction except as hereinafter pointed out, comprising the base a, standard or frame 6 and arm 0 depending from the standard and in which is mounted reciprocably the needle bar cl and the presser bar 6, the latter being controlled, as usual, either by a cam lever e or an operating rod 6 attached to a rocking arm a the free end of which engages a stud a on the presser bar 6 when the operating rod 6 is drawn downwardly as by a foot treadle, not illustrated.

The main driving shaft f of the machine drives, through the usual pitman f, a rock shaft f mounted on the standard Z) and connected by an arm f and link f with the needle bar 01. I Since the pitman f is connected through an eccentric, as usual, with the main driving shaft 7, it will be understood that reciprocation of the pitman will serve to impart a rocking movement to the rock shaft f thus reciprocating the needle bar as usual. This needle bar, especially in the heavier types of machines, is of no little mass and the number of its-reciprocations, especially in power-driven machines, is great. Consequently, the momentum of the needle bar at is very 'great at times and in fact, unless its speed is limited the entire machine may be entirely deranged by its pounding. In accordance with the present invention the rock shaft f as shown most clearly in Fig. 4:, rocks against the action of a spiral spring g which encircles the rock shaft and has one end anchored in the standard b and the other end secured as through an adjustable collar h to the rock shaft. The entire spring 9 may be protected by a suitable incasing sleeve 72. secured to the collar it. The position of this collar h and sleeve h with respect to the rock shaft f may be fixed by a suitable set screw 2'. It will be evident that the effective tension of the spring 9 is determined by the position which the collar 5 is given on the rock shaft f When the needle bar travels downwardly,

for instance, under the impelling force given by the rock shaft f its downward travel is opposed by the spring g and this opposition increases constantly until the needle bar has reached its lowermost position. When the needle bar reaches its lowermost position its momentum will be counter-balanced in large measure by the spring 9 and its reversal of travel will not be accompanied by the usual pounding hitherto experienced.

Since its momentum depends upon its mass and its velocity, the spring counter-balance may be adjusted as hereinbefore explained for difierent conditions of use and for different machines.

I11 the present invention, the operating rock shaft f for the needle bar is used to actuate positively a tension device -whereby.

the thread is released periodically from the tension of a s )ring which normally presses it against the frame of the machine. -As indicated in Figs. 3 and 4, the rock shaft f? carries thereon a sleeve j in which is pivotally mounted a stifl wire or rod 70 so bent as to extend in substantially a horizontal plane through a suitable aperture or channel formed in the frame or standard I). The free end of the wirelais disposed to engage periodically a leaf spring Z secured to the front face of the frame b and arranged to press the thread normally against the face of the frame. The collar j may be provided with a set screw so that its position on the rock shaft 7 may be changed at will and the effective travel of the wire k. with respect to the tension spring Z adjusted. "In this waythe thread may be subjected to greater or less tension at the time of its feed.

The feeder m is given a combined horizontal and vertical oscillating movement so that it will engage and feed forward the material at the proper time. This movement is impartedcto the feeder m by substantially the same'general means as have been formerly employed.

The main shaft f has secured thereto through an eccentric connect-ion an operating rod f*, the free end of which is in adjustable connection with a slotted arm to in operative connection with the shaft m on which the feeder m is pivotally supported. By reason of the eccentricity of the rod f theshaftm on which the feeder m is pivotally supported, is given an oscillating movement. The range of this movement may be varied by adjusting the slotted arm to with respect to the eccentric arm f*.

.The usual looper 79 may be mounted in theend of the shaft 7".

.The work plate q is mounted on the base aofthe machine inthe, usual manner and has secured to it the work gage orguide. The latter comprises a main member 1" slotted, as at r, to permit its adjustment with respect to the work plate 9 throughthe supporting stud 1. The end of the mainmember 1 is'provided with adepending lip or flange 1' to engage the work and guide it in citSrtravel. This main member '1' has secured trated and described will suggest themselves but all such modified constructions and arrangements are-to be deemed within the scope of this invention provided they fall within the terms of the claims appended hereto.

I claim as myinvention:

1. In a'sewing machine, the combination of a main drive shaft, a rock shaft, areciprocating needlebar, operative connections between vthevrockv shaft and the. drive shaft and theneedle bar respectively and. a torsional counter-balancing spring. operatively connected to the rock shaft at one end and fixedat the other end. whereby oscillations of the rockashaftineone. direction are opposed by the spring, and'in the reverse direction assisted thereby.

2. In a sewing machine, the combination of a supporting frame, a main drive shaft, a rock shaft bearing in the .supporting frame, a reciprocating needle bar, operative connections'between therock shaft and the drive shaft and the needle bar respectively, a collar adj ustably secured on the rock shaft,

and a counter-balancing spring encircling the rock shaft-and having one end secured to the collar and the other end anchored in the supporting frame.

3. -In a sewing machine, the combination of a supporting frame, a main driveshaft, a

rock shaft bearing in the supporting frame, a reciprocating needle bar, operative connections between the rock shaft and the drive shaft and theneedle bar respectively, a collar adjuistabily secured on the rock shaft, a counter-balancing spring encircling the rock shaft and having one end secured to the collar and the other end anchored in the supporting frame, and a sleeve to inclose the spring.

This specification signed and witnessed this first day of July A. D. 1913.

LOUIS BULASKY. Signed in the presence of B. GREELEY, VVORTHINGTON CAMPBELL.

Copies of thispatent may be obtained for five cents each, by addressing. the Commissioner of Patents,

Washington, D. G. 

